An audio tape said to have been recorded by al-Qaeda leader Osama Bin Laden has called on his supporters to attack Gulf oil supplies.

The recording, posted on an Islamic website, has not been verified.

In the message a speaker identified as Bin Laden also praised the attack by a group of militants on a US consulate in Saudi Arabia on 6 December.

The voice blamed Saudi leaders for unrest in the kingdom, accusing them of "violating God's rules".

Earlier this month Pakistani President Pervez Musharraf said recent intelligence proved that the al-Qaeda leader was alive - but he said the trail was "completely cold".

'Mercy for mujahideen'

"Targeting America in Iraq in terms of economy and loss of life is a golden and unique opportunity... Be active and prevent them from reaching the oil, and mount your operations accordingly, particulary in Iraq and the Gulf," the speaker said.

The thief is taking the money of the Iraqi people and violating their land and honour, backed by the support and advice of the Arabian ruler

The speaker also said: "We ask God Almighty to have mercy on the mujahideen who stormed the consulate of the Americans in Jeddah."

Saudi Arabia has been battling a wave of attacks in the past 18 months, which it blames on the al-Qaeda network.

Nine people, including four militants, were killed when militants stormed the US building in Jeddah on 6 December. A fifth militant was arrested at the scene of the attack, which was claimed by the group.

Saudi-born Bin Laden has repeatedly called for the toppling of the kingdom's ruling family.

"The responsibility for the current situation in Saudi Arabia rests with the regime," the recording said, according to AFP news agency.